Electric condenser



July 3, 1923. Re. 15,642; I C. F. SMITH ET AL ELECTRI C C ONDENSER' Original Filed May 17. 1920 344/00" bow Reiuued July 3, 1923.

CHARLES 1. SMITH AND WILLIAM SKITH, OF BROOKLYN, NEW YORK.

ELECTRIC commnsan.

original No. 1,898,981, dated November ,1, 1921, Serial No. 982,090, filed m 17, 1920. Application for relllue filed October 13, 1922. Serial No. 594,391.

character. and also an improved method for the easy and expeditious making of such condensers. Condensers of our improved type are intended primarilyfor use in wireless telegraphy or telephony but they are also adapted for other uses.

A satisfactory embodiment of a condenser made according to our invention is shown in the accompanying drawing. .The condenser there'illustrated comprises units any number of which may be assembled readily to form a condenser of -the desired capacity. Each of the units shown comprises a base or body portion which gives the unit the requisite strength or stiffness; a flexible dielectric, preferably paper impregnated with insulatlng material, such as wax; and sheets of metal foil preferabl non-resilient metal, such as lead ortin foil, though other metal foils may be used ;'such dielectric and metal foils being folded or wrapped-together.

A desirable embodiment of our invention is shown in the accompanying drawings, in

which- Fig. 1 is a detail view of the base or body portion of a condenser unit Fig. 2, is aperspective VIEW" 'showlng the 40 manner ofassembling the metal foil and flexible insulating sheets of the unit.

Fig. 3, is a perspective view of a completed unit.

Figs. 4 and 5 are longitudinal and transverse sections, respectively, of the improved condenser unit.

Fig. 6 is an elevation showing a number of condenser units suitably mounted.

each of the halves or (pilies of the folded di- Referring to the drawing, in which some of the thin parts are necessarily somewhat exaggerated for. clearness of illustration, 12

denotes the base or body ortion of the imhas thev requisite stiffness and also offers the advantage that it is not softened or affected Y by moisture, as ordinar pasteboard would be. Adjacent to its en s, the body ortion 12 is provided with holes 13, adapte to receive e elets 14, as more fully set forth below. 0 make the improved condenser shown in the drawing, we then take a strip of flexible dielectric 15, for instance waxed paper, and fold it upon itself at the center, as indicated in Fig. 2; a sheet of metal foil 16, with a lead 17 projecting therefrom at one side, is placed between the two layers of the folded or doubled sheet of dielectric 15, so that the same surface of said sheet 15 (the inner surface) will be adapted to engage both surfaces the upper and the lower surface) of said s eet of metal foil 16. ,On top of the folded dielectric sheet 15, so as to be in contact with its upper or outer surface, is placed a second sheet of metal foil 18, simi lar to the sheet16, except that the lead 19 of the sheet 18 and the lead 17 of the sheet 16 project from the folded dielectric sheet 15 at opposite sides thereof. The sheets 16 and 18 of 'metal foil are smaller in size than electric, so that the e ges ofthe latter extend beyond the sheets of metal foil to prevent short-circuitin Preferably as shown in Fig. 2, tlhe leads 1%, 19 are placed adjacent to the fold connecting the two-plies ofthe dielectric sheet 15; this gives them a more protected position during the wrapping of the dielectric and of the metal foil. While we have shown these 17, 19 as integral with the respective metal foil sheets 16 and 18, no

this is not essential.

said body portion 12 in such a manner that In the form of our invention illustrated, and .more particularly with reference to Figs. 4 and 5, vthe folded dielectric sheet 15 and the two metal sheets 16,18 are wrapped in a somewhat spiral way, about the base or body portion 12, it bein noted that the latter is lon r than the eet 15, so that the ends of t e body portion will roject beyond the said sheets 15 when the atter, with the two sheets of metal foil 16, 18 is placed against the central part of the body rtion 12, see Figs. 3, 4. 5 and 6. Prefera ly the parts shown in Fig. 2, are placed against the fold or crease 15' will lie adjacent to one of the longitudinal edges of said body. Then, inthe particular procedure which results in the production of the article or unit here shown, the parts shown inFig. 2, are wrapped around the body portion 12, so that the latter will, as it were, form a core surrounded by such wrapped parts, the

leads 17, 19, however, remaining unwrapped,

as they are applied flatwise a ainst the one surface (the upper surface'in ig. 4) of the body rtion 12. If desired the leads 17, 19 may it: of considerably greater area than that of the projecting ends of the body por- .mounted nuts 24, to be screwed up tion 12, so that they can be folded around said projecting ends. In thisbase'the leads are lon r than the ends and are folded over the en of the said base or body portion, so that each lead extends around over both surfaces of one end of the body portion, as shown in Fi 4. The-wrappings of metal foil and diefiactric are then surroundedor covered by a paster or plasters 20, of thin muslin or other sheet material, whereby the said wrappings are securely held in place on the body 12 of the condenser unit. Eyelets 14, referably of brass, are then inserted in the oles 13 of the base or body portion 12, said eyelets passing through both the upper and the lower layer of the folded lead 17 or 19, and thus serving to secure said leads firmly about and against both surfaces of the body portion.

These units may be secured in the electrical circuit in any desired way. As illustrate ed in the drawings, theeyelets serve for the reception of screws or bolts 22, on which are against the lower side of the'body 12, or rather of the eyelets 14, of the lowermost condenser unit when a number of the units are assembled, as shown in Fig. 6. The said screws or bolts 22'are also preferably provided with nuts 25, by which the assembled condenser units may be fastened to a suitable panel or the like when the condenser is mounted in place for use. The cogndenser units are spaced apart on the screws or bolts 22 by collars or sleeves 23 forming distance ieces. It will be understood that the assem ly of condenser units as' shown in Fig. 6, afiords a convenient manner of utilizing the invention, as each unit is, in itself, a complete condenser.

The improved condensers or condenser units, when completed, are tested by a microfarad meter, and each unit or grid is labeled, to show capacity, which is determined by the length of the body and breadth and thickness of thewaxed paper dielectric. v

From the foregoing it will be understood that the invention provides an electric eondenser 'of.,sim le construction which has very efiicient and durable igures 2, 4 and 5 in order to ma e illus-- tration possible. To those skilled, however,

it will be obvious that the twelve thicknesses of paper and foil shown in Figs. 4 and 5,- actually aggregate less than 1/32nd of an inch in thickness, hence the middle portion of. the base. 12, is racticall necessaryas a stifl'ening means or the 0 ded aper'andfoil constituting the condenser, ust as the pro'ecting ends serve as stiffening means to w ich leads 17 19 are riveted.

We claim as our invention:

1. An electric condenser unit comprising a base or bod of thin fiberboard and a wrapping of' ielectric and metal foil encircling said base or body, the sheets of metal foil being smaller n size than the sheets or plies of dielectric, said sheets of metal foil having leads which are folded around theends of the fiber base or body, and means for securin the wra ping of dielectric and metal foi in place a ut said base or body.

2. An electric condenser unit comprising a base or body of thin fiber board and a wrappin of dielectric waxed. paper and .metal foil'encircling said base or body, the

sheets of metal foil being smaller in size than the sheets or plies of waxed paper, said sheets of'metal foil havin leads which are folded around the ends 0 the fiber base or body, and means for securing the wrap ing of ielectric and metal foil in place about said base or body. V

3. An electric condenser unit comprising a base or body of thin fiber board and a wrappi of dielectric waxed paper and metal foil encirclin sheets of metal foil being smaller in size than the sheets or plies of waxed paper, said said base or body, the I sheets of metal foil havin leads which are folded around the ends 0 the fiber base or body, and a securing wrapper o r-paster passing around the wrapping of waxed paper and metal foil.

4. An electric condenser comprising a base or bod of thin fiber board and a wrapping of dielectric and metal foil encircling said base or body, the sheets of metal foil being smaller in size than the sheets or plies of dielectric, said sheets of metal foil having metal foil leads which are folded around the ends of the fiber base or body, and means for securing the wrapping of dielectric and metal foil in place about said base or body.

5, An electric condenser comprising a relatively long. narrow, thin base or body of relatively stiff insulating material and a wrappin of flexible dielectric sheets and metal foll encircling said base or body; the

sheets of metal foil being smaller in size than the dielectric sheets; the body or base being substantially longer than the width of the wrapping sheets to afford projecting ends; and said sheets of metal foil having leads projecting in opposite directions and each secured to the face of the correspond-- ing end of the base; and means for securing the wrapping of dielectric and metal foil in place about said base.

6. An electric condenser comprising a relativel long, narrow base. or body of thin fiber board and a wrapping of flexible dielectricsheets and thin metal or foil encircling said base or body between projecting ends of the latter, the sheets of metal fo l be' narrower and shorter than the sheets of 'electric; and terminals consisting of thin metal or foil, one secured against a face of a projecting end of the base or body and conductively assmiated with one sheet of the foil and the other terminalsimilarly secured to the other projecting end and similarly associated with the other sheet of foil.

7. An electric condenser com rising a wrapping of metal foils and of exible dielectric interposed between said foils, a relatively stifl' body the ends of which project beyond said wrapping, conducting leads which extend from said foils adjacent to said ends of the body, and which are folded over said ends so that each lead will have layers on opposite sides of the respective body end, and securing means extending through said body ends and through both layers of the 1 respective folded leads.

8. An electric condenser comprising a. wrapping of metal foils and of flexible dielectric interposed between said foils, a relatively stiff body the ends of which project .beyond said wrapping conducting leads which extend from said foils adjacent to said ends of the body, and eyelets extendin through said body ends and through the a jfi lads to e u e he latter firmly tosald body and to provide means for the reception of screws or bolts serving to assemble a plurality of condenser units.

9. An electric condenser comprisin wrapping which consists of a sheet of exible dielectric' folded upon itself to form two plies, a metal foil located between the plies of such folded dielectric, another metal foil located on the side of the dielectric opsite to the first named foil, a supporting dy for said wra ping, and leads extending fromsaid metal oils. 7

10. An' electric condenser comprising a. wrap ing which consists of asheet of flexible ielectric folded upon itself to form two plies, a metal foil located between the plies of such folded dielectric, another metal foil located on the side of the dielectric opposite to the first named foil, and leads extending from said metal foils.

11. An e ectric condenser comprising a wrapping which consists of a sheet of flexible dielectric folded upon itself to form two plies, a metal foil located between the plies of such folded dielectric, another metal foil located on the side of the dielectric opposite to the first named foil, a, supporting body projecting beyond said wrapping at each end, leads connected with said metal foils and extendin adjacent. to the projecting ends of said 7 y, and meansfor securing said leads firmly to said body ends.

12. An electric condenser comprising thin sheets of metal foil separated b thin flexi ble di-electric, assembled as a relatively thin and flexible condenser element in combination with a stiffening support therefor consisting of a relatively thin stifl' body of insulatin material having portions thereof projecting beyond said assembled sheets, conducting leads from the foil sheets and terminals therefor consisting of hollow eyelets riveted through said stiffening support.

13. An electric condenser comprisi thin metal foils separated by thin flexib e di' electric sheets wrapped around a relatively thin stiff body of insulating material, the ends of which project beyond said wrapping, conductingleads res tively riveted to opposite projecting en s of said body and extending in conducting relation with different sheets of said metal foil.

14. An electric condenser comprisin thin metal foils separated by thin flexible ielectric sheets wrapped around a relatively thin stifl' body of insulati .material the ends of which project beyon said wra ping, conducting leads respectivel rivet to opposite rojectmg ends'of said y and extending tween the dielectric sheets, each in conlurlaging relation-with one only of said metal 01 15. An electric condenser comprising-two sheets of thin metal foils separated by two sheets of flexible dielectric and the four lln folded together to form a, thin narrow condenser element, a relatively stifi body of insulating material the ends of which project beyond said condenser element, an external 5 wrapper securing said condenser element to said relatively stifi body and conducting leads respectively riveted to the opposite projecting ends of said body and extending between the dielectric sheets, each conductively connected with one only of said metal 10 foil sheets.

Signed in NewnYork City, count State of New York, this 21st day 0 tember, 1922.

and Sep- CHARLES F. SMITH. WILLIAM H. SMITH. 

